Hmmm........... thinking about this just now, at the end of a very long day, and the end of a very long week (so my logic is probably pretty flawed right now)
we are not up-voting or up-steeming.
The 'vote' does not push the content higher in the list (hot or trending, or my feed etc) and it doesn't add to its 'steemyness'.
What it does do is pay the author. So maybe it should be something like 'tip the author', 'fund this author', 'appreciate this post'
That tells new people exactly what they are doing when they click the button.
Or - upsteeming makes complete sense too :-)
I totally get long days, especially lately, work was piling up. So I understand :)